All-time weather records — Swansea, IL
Climate change signal in Swansea
of Swansea's all-time daily heat records were set in the last decade (45 of 366 records since 2015).
of all-time daily cold records were set in the last decade (26 of 366 records since 2015).
If records were spread evenly across the station's history, you'd expect roughly 5% per decade. Decade-by-decade, here's where each record-breaking day was set:
| Decade | Heat records set | # | Cold records set | # |
|---|---|---|---|---|
| 1940s | 6 | 1 | ||
| 1950s | 76 | 17 | ||
| 1960s | 41 | 80 | ||
| 1970s | 23 | 71 | ||
| 1980s | 47 | 88 | ||
| 1990s | 34 | 47 | ||
| 2000s | 49 | 21 | ||
| 2010s | 76 | 20 | ||
| 2020s | 14 | 21 |
Records are the all-time daily extremes that are still standing — each daily record can only be held by one year. The station's earliest hot record was set in 1948, the latest in 2026. Period of observation: 1948-2026.
Records by month
| Month | Hottest day | Coldest day | Wettest day |
|---|---|---|---|
| January | 75.0°F — Jan 24, 1950 | -27.0°F — Jan 17, 1977 | 3.58 in — Jan 3, 1950 |
| February | 82.9°F — Feb 15, 2018 | -20.9°F — Feb 10, 1982 | 4.48 in — Feb 2, 1986 |
| March | 89.1°F — Mar 21, 1997 | -8.0°F — Mar 5, 1978 | 2.68 in — Mar 19, 2008 |
| April | 91.0°F — Apr 14, 2006 | 18.0°F — Apr 8, 2007 | 4.58 in — Apr 29, 1996 |
| May | 97.0°F — May 26, 1953 | 28.0°F — May 4, 1976 | 4.57 in — May 17, 1995 |
| June | 106.0°F — Jun 28, 2012 | 37.9°F — Jun 1, 1972 | 8.15 in — Jun 15, 1957 |
| July | 109.9°F — Jul 14, 1954 | 43.0°F — Jul 6, 1972 | 3.93 in — Jul 28, 1979 |
| August | 105.1°F — Aug 15, 2007 | 39.0°F — Aug 29, 1986 | 4.00 in — Aug 12, 2020 |
| September | 102.9°F — Sep 5, 1954 | 26.1°F — Sep 23, 1995 | 4.17 in — Sep 8, 2018 |
| October | 96.1°F — Oct 1, 2019 | 19.0°F — Oct 17, 2024 | 3.45 in — Oct 30, 2009 |
| November | 84.0°F — Nov 1, 1950 | 1.9°F — Nov 8, 1991 | 4.50 in — Nov 6, 2024 |
| December | 77.5°F — Dec 28, 2025 | -18.9°F — Dec 22, 1989 | 3.97 in — Dec 3, 1982 |
Click a month to see every daily record for that month in Swansea.